-
外観
無色澄明の液体ハーゼン10以下
-
溶解性
エタノール及びジエチルエーテルに極めて溶けやすく、水にやや溶けにくい。
-
解説
ジクロロメタン，融点－96.8 ℃，沸点40.21 ℃．d413"1.335．nD20"1.4244．有機化合物の抽出および反応溶剤，洗浄剤，冷媒などに広く利用される．
森北出版「化学辞典（第2版）
-
用途
洗浄剤(プリント基板,金属脱脂)、医薬·農薬溶剤、エアゾール噴射剤、塗料剥離剤、ポリカーボネートの反応溶剤、ウレタンフォーム発泡助剤、繊維?フィルム溶剤、接着剤、ペイントはく離剤、プリント基板洗浄剤、低沸点用有機溶剤。
-
用途
精密分析、超高純度溶剤として個人専用試薬。
-
用途
液体クロマトグラフ分析における溶離液及び溶離液調製用原料。
-
用途
ペプチド合成用溶媒。
-
用途
生体試料中等のダイオキシン類の分析における溶媒。
-
用途
汎用試薬、高純度を必要とする低沸点溶剤等。
-
用途
汎用試薬、低沸点溶剤。
-
効能
溶解剤
-
製造
塩化メチレンともいう．塩化メチルを塩素化するか，クロロホルムを亜鉛と酢酸で還元すると得られるジクロロメタン．
-
主な用途／役割
溶剤型接着剤、エアゾール接着剤、はがし液に使用される
-
使用上の注意
不活性ガス封入
-
説明
Dichloromethane is a colorless liquid with an ethereal, but penetrating odor. Its miscibility in alcohol and ether and slight solubility in water has made it an ideal solvent and otherwise extremely versatile chemical. It has been used industrially (solvent and paint remover), as a drug (inhalation anesthetic) and as an agricultural chemical (growth regulator and fertilizer). It is narcotic in high concentrations and carcinogenic. Inhalation exposure to this substance irritates the nose and throat and affects the central nervous system.
-
化学的特性
Dichloromethane is a colorless liquid with a mild, sweet odor. It does not occur naturally in the environment. It is made from methane gas or wood alcohol. Industrial uses of dichloromethane are extensive, as a solvent in paint strippers, as a propellant in aerosols, and as a process solvent in the manufacturing of drugs. dichloromethane is also used as a metal cleaning and fi nishing solvent, and it is approved as an extraction solvent for spices and hops. Exposure to dichloromethane occurs in workplaces by breathing fumes from paint strippers that contain it (check the label), breathing fumes from aerosol cans that use it (check the label), and breathing contaminated air near waste sites.
-
物理的性質
Clear, colorless liquid with a sweet, penetrating, ethereal odor. Leonardos et al. (1969) determined
an odor threshold concentration of 214.0 ppmv. The average least detectable odor threshold
concentrations of technical grade methylene chloride in water at 60 °C and in air at 40 °C were 5.6
and 24 mg/L, respectively (Alexander et al., 1982).
-
使用
Dichloromethane, also called methylene chloride, is widely used as a solvent, as a degreasing and cleaning reagent, in paint removers, and in extractions oforganic compounds from water for analyses.
-
調製方法
Dichloromethane was first prepared by Regnault in 1840 by the chlorination of methyl chloride in sunlight. It became an industrial chemical of importance during the Second World War. Two commercial processes are currently used for the production of dichloromethane—hydrochlorination of methanol and direct chlorination of methane (Rossberg et al., 1986; Holbrook, 1993). The predominant method of manufacturing dichloromethane uses as a first step the reaction of hydrogen chloride and methanol to give methyl chloride. Excess methyl chloride is then mixed with chlorine and reacts to give dichloromethane, with chloroform and carbon tetrachloride as co-products. This reaction is usually carried out in the gas phase thermally but can also be performed catalytically or photolytically. At low temperature and high pressure, the liquid-phase process is capable of giving high selectivity for dichloromethane (Rossberg et al., 1986; Holbrook, 1993).
-
反応性
Methylene chloride reacts violently in the presence of alkali or alkaline earth metals and will hydrolyze to formaldehyde in the presence of an aqueous base. Alkylation reactions occur at both functions, thus di-substitutions result.
-
一般的な説明
Dichloromethane has been tested as a solvent medium for the dipyridine-chromium(VI) oxide. Solubility was reported to be 12.5g/100ml. Role of quantity of TiO2 loading on activated carbon support employed in the photodecomposition of dichloromethane has been investigated.
-
空気と水の反応
Methylene chloride is a colourless liquid with a mild, sweet odour. Somewhat water soluble. Subject to slow hydrolysis which is accelerated by light.
-
反応プロフィール
Dichloromethane reacts vigorously with active metals such as lithium, sodium and potassium, and with strong bases such as potassium tert-butoxide. Dichloromethane is incompatible with strong oxidizers, strong caustics and chemically active metals such as aluminum or magnesium powders. The liquid will attack some forms of plastic, rubber and coatings. Dichloromethane reacts with sodium-potassium alloy, (potassium hydrogen + N-methyl-N-nitrosurea), nitrogen tetraoxide and liquid oxygen. Dichloromethane also reacts with titanium. On contact with water Dichloromethane corrodes iron, some stainless steels, copper and nickel. Dichloromethane is incompatible with alkali metals. Dichloromethane is incompatible with amines, zinc and alloys of aluminum, magnesium and zinc. Dichloromethane is liable to explode when mixed with dinitrogen pentaoxide or nitric acid. Mixtures of Dichloromethane in air with methanol vapor are flammable.
-
危険性
Toxic. A narcotic. Central nervous systemimpairment and carboxyhemoglobinemia. Possiblecarcinogen.
-
健康ハザード
Dichloromethane is classified as only slightly toxic by the oral and inhalation routes.
Exposure to high concentrations of dichloromethane vapor (>500 ppm for 8 h) can
lead to lightheadedness, fatigue, weakness, and nausea. Contact of the compound
with the eyes causes painful irritation and can lead to conjunctivitis and corneal
injury if not promptly removed by washing. Dichloromethane is a mild skin irritant,
and upon prolonged contact (e.g., under the cover of clothing or shoes) can cause
burns after 30 to 60 min exposure.
Dichloromethane is not teratogenic at levels up to 4500 ppm or embryotoxic in rats
and mice at levels up to 1250 ppm.
-
火災危険
Special Hazards of Combustion Products: Dissociation products generated in a fire may be irritating or toxic.
-
燃焼性と爆発性
Noncombustible. Dichloromethane vapor concentrated in a confined or poorly ventilated area can be ignited with a high-energy spark, flame, or high-intensity heat source.
-
化学反応性
Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.
-
安全性プロファイル
Confirmed carcinogen
with experimental carcinogenic and
tumorigenic data. Poison by intravenous
route. Moderately toxic by ingestion,
subcutaneous, and intraperitoneal routes.
Mildly toxic by inhalation. Human systemic
effects by ingestion and inhalation:
paresthesia, somnolence, altered sleep time, convulsions, euphoria, and change in cardlac
rate. An experimental teratogen.
Experimental reproductive effects. An eye
and severe skin irritant. Human mutation
data reported. It is flammable in the range of
12-19% in air but ignition is difficult. It will
not form explosive mixtures with air at
ordinary temperatures. Mixtures in air with
methanol vapor are flammable. It will form
explosive mixtures with an atmosphere
having a high oxygen content, in liquid O2,
N2O4, K, Na, NaK. Explosive in the form
of vapor when exposed to heat or flame.
Reacts violently with Li, NaK, potassiumtert-
butoxide, (KOH + N-methyl-Nnitrosourea).
It can be decomposed by
contact with hot surfaces and open flame,
and then yield toxic fumes that are irritating
and give warning of their presence. When
heated to decomposition it emits highly
toxic fumes of phosgene and Cl-.
-
職業ばく露
Methylene chloride is used mainly as
a low-temperature extractant of substances which are
adversely affected by high temperature. It can be used
as a solvent for oil, fats, waxes, bitumen, cellulose acetate;
and esters. It is also used as a paint remover;
as a degreaser; and in aerosol propellants
-
発がん性
Dichloromethane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
-
輸送方法
UN1593Dichloromethane, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials
-
純化方法
Shake it with portions of conc H2SO4 until the acid layer remains colourless, then wash with water, aqueous 5% Na2CO3, NaHCO3 or NaOH, then water again. Pre-dry with CaCl2, and distil it from CaSO4, CaH2 or P2O5. Store it away from bright light in a brown bottle with Linde type 4A molecular sieves, in an atmosphere of dry N2. Other purification steps include washing with aqueous Na2S2O3, passage through a column of silica gel, and removal of carbonyl-containing impurities as described under Chloroform. It has also been purified by treatment with basic alumina, distillation, and stored over molecular sieves under nitrogen [Puchot et al. J Am Chem Soc 108 2353 1986]. Dichloromethane from Japanese sources contained MeOH as stabiliser which is not removed by distillation. It can, however, be removed by standing over activated 3A Molecular Sieves (note that 4A Sieves cause the development of pressure in bottles), passed through activated Al2O3 and distilled [Gao et al. J Am Chem Soc 109 5771 1987]. It has been fractionated through a platinum spinning band column, degassed, and distilled onto degassed molecular sieves Linde 4A (heated under high vacuum at over 450o until the pressure readings reached the low values of 10-6 mm, ~1-2hours ). Stabilise it with 0.02% of 2,6-di-tert-butyl-p-cresol [Mohammad & Kosower J Am Chem Soc 93 2713 1971]. [Beilstein 1 IV 35.] Rapid purification: Reflux over CaH2 (5% w/v) and distil it. Store it over 4A molecular sieves.
-
不和合性
Incompatible with strong oxidizers,
caustics; chemically active metals, such as aluminum,
magnesium powders; potassium, lithium, and sodium;
concentrated nitric acid causing fire and explosion hazard.
Contact with hot surfaces or flames causes decomposition
producing fumes of hydrogen chloride and phosgene gas.
Attacks some forms of plastics, rubber and coatings.
Attacks metals in the presence of moisture.
-
廃棄物の処理
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform to EPA regulations
governing storage, transportation, treatment, and waste
disposal. Incineration, preferably after mixing with
another combustible fuel; care must be exercised to
assure complete combustion to prevent the formation
of phosgene; an acid scrubber is necessary to remove the
halo acids produced.
